Find all School-related info fast with the new School-Specific MBA Forum

It is currently 24 Oct 2014, 00:17

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

At the end of 2004, a certain farm had 24 hens, 12 cows, 30

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Expert Post
1 KUDOS received
Moderator
Moderator
User avatar
Joined: 01 Sep 2010
Posts: 2441
Followers: 312

Kudos [?]: 2619 [1] , given: 696

At the end of 2004, a certain farm had 24 hens, 12 cows, 30 [#permalink] New post 07 Mar 2012, 13:23
1
This post received
KUDOS
Expert's post
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

56% (04:16) correct 44% (02:46) wrong based on 61 sessions
At the end of 2004, a certain farm had 24 hens, 12 cows, 30 sheep, and 14 pigs. By the end of 2005, 22 new animals — each either a hen, cow, sheep or pig — were brought to the farm. No animals left the farm. How many pigs were there on the farm at the end of 2005?

(1) The ratio of cows to pigs and the ratio of hens to sheep were the same at the end of 2004 and 2005.
(2) The number of sheep increased by 1/6 from the end of 2004 to the end of 2005
_________________

COLLECTION OF QUESTIONS
Quant: 1. Bunuel Signature Collection - The Next Generation 2. Bunuel Signature Collection ALL-IN-ONE WITH SOLUTIONS 3. Veritas Prep Blog PDF Version
Verbal:1. Best EXTERNAL resources to tackle the GMAT Verbal Section 2. e-GMAT's ALL CR topics-Consolidated 3. New Critical Reasoning question bank by carcass 4. Meaning/Clarity SC Question Bank by Carcass_Souvik 5. e-GMAT's ALL SC topics-Consolidated-2nd Edition 6. The best reading to improve Reading Comprehension 7.Verbal question bank and Directories


Last edited by Bunuel on 07 Mar 2012, 14:06, edited 2 times in total.
Edited the question
Expert Post
7 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 23398
Followers: 3611

Kudos [?]: 28865 [7] , given: 2854

Re: Ratio of x-y-z-w [#permalink] New post 07 Mar 2012, 13:58
7
This post received
KUDOS
Expert's post
At the end of 2004, a certain farm had 24 hens, 12 cows, 30 sheep, and 14 pigs. By the end of 2005, 22 new animals — each either a hen, cow, sheep or pig — were brought to the farm. No animals left the farm. How many pigs were there on the farm at the end of 2005?

(1) The ratio of cows to pigs and the ratio of hens to sheep were the same at the end of 2004 and 2005.

At the end of 2004 the ratio of cows to pigs was 12/14=6/7, in order the ratio to remain the same at the end of 2005, cows and pigs should be added in the same ratio (or not added at all). So, possible numbers of new cows and pigs are: (0, 0) or (6, 7). Notice that (12, 14) is not possible since 12+14=26, which is more than total number of new animals brought, 22.

The same for the ratio of hens to sheep: at the end of 2004 the ratio was 24/30=4/5. So, possible numbers of new hens and sheep are: (0, 0), (4, 5) or (8, 10).

Only one combination makes total of 22 animals: (6, 7) and (4, 5) --> 6+7+4+5=22. Hence, 7 new pigs were brought to the farm, so there were 14+7=21 pigs on the farm at the end of 2005. Sufficient.

(2) The number of sheep increased by 1/6 from the end of 2004 to the end of 2005. 5 sheep were brought to the farm, but we know nothing about the rest of 17 animals. Not sufficient.

Answer: A.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
25 extra-hard Quant Tests

Get the best GMAT Prep Resources with GMAT Club Premium Membership

Expert Post
Moderator
Moderator
User avatar
Joined: 01 Sep 2010
Posts: 2441
Followers: 312

Kudos [?]: 2619 [0], given: 696

Re: At the end of 2004, a certain farm had 24 hens, 12 cows, 30 [#permalink] New post 07 Mar 2012, 14:32
Expert's post
Cool

I changed the animals with variables to make it look more difficult, muddy the waters.

I think that when you realize that you have the relationship between ratios is already clear sufficient and move on is the right thing but your deep explanation is always useful to understand.

Next time I'll post the question correctly, eventhough it was the same thing.

Thanks Bunuel.

PS: OA is A
_________________

COLLECTION OF QUESTIONS
Quant: 1. Bunuel Signature Collection - The Next Generation 2. Bunuel Signature Collection ALL-IN-ONE WITH SOLUTIONS 3. Veritas Prep Blog PDF Version
Verbal:1. Best EXTERNAL resources to tackle the GMAT Verbal Section 2. e-GMAT's ALL CR topics-Consolidated 3. New Critical Reasoning question bank by carcass 4. Meaning/Clarity SC Question Bank by Carcass_Souvik 5. e-GMAT's ALL SC topics-Consolidated-2nd Edition 6. The best reading to improve Reading Comprehension 7.Verbal question bank and Directories

Intern
Intern
avatar
Joined: 22 Jan 2012
Posts: 6
Followers: 0

Kudos [?]: 2 [0], given: 1

Re: At the end of 2004, a certain farm had 24 hens, 12 cows, 30 [#permalink] New post 08 Mar 2012, 04:25
it is said that we do not have to solve the DS questions. As can be seen, however, this is not the case for most of the time, especially after going through Bunuel's solutions:) Thanks for the solution.
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 23398
Followers: 3611

Kudos [?]: 28865 [0], given: 2854

Re: At the end of 2004, a certain farm had 24 hens, 12 cows, 30 [#permalink] New post 24 Jun 2013, 02:17
Expert's post
Bumping for review and further discussion*. Get a kudos point for an alternative solution!

*New project from GMAT Club!!! Check HERE

All DS Fractions/Ratios/Decimals questions: search.php?search_id=tag&tag_id=36
All PS Fractions/Ratios/Decimals questions: search.php?search_id=tag&tag_id=57

_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
25 extra-hard Quant Tests

Get the best GMAT Prep Resources with GMAT Club Premium Membership

1 KUDOS received
Intern
Intern
avatar
Joined: 22 May 2013
Posts: 49
Concentration: General Management, Technology
GPA: 3.9
WE: Information Technology (Computer Software)
Followers: 0

Kudos [?]: 11 [1] , given: 10

GMAT ToolKit User
Re: At the end of 2004, a certain farm had 24 hens, 12 cows, 30 [#permalink] New post 25 Jun 2013, 07:16
1
This post received
KUDOS
Bunuel wrote:
Bumping for review and further discussion*. Get a kudos point for an alternative solution!

*New project from GMAT Club!!! Check HERE

All DS Fractions/Ratios/Decimals questions: search.php?search_id=tag&tag_id=36
All PS Fractions/Ratios/Decimals questions: search.php?search_id=tag&tag_id=57


Questtion :
Total no of animals in farm currently = 80
H=24, C=1, S=30, P=14

(1) The ratio of cows to pigs and the ratio of hens to sheep were the same at the end of 2004 and 2005.
C/P and H/S will be the same for 2004 and 2005 respectively.

Hence for 2004 :
C/P = 12/14 = 6/7 Hence, the multiplication factor for the ratio = x =2
H/S = 24/30 =4/5 Hence, the multiplication factor for the ratio = y = 6

Since the no of animals inc by 22 and none of the animals leave the farm, the new factors say x' and y' will be such that x'>=x or y'>=y

hence,
6x'+7x'+4y'+5y' = 80+22
13x'+9y'=102

trying with the first combination say, x'=3 and y'=7
39 + 63 = 102
102 = 102 (Bingo!!)

Thus, x' = 3 and y'=7
Therefore no of pigs = 7x' = 21
so, 7 new pigs were added
=>Sufficient

(2) The number of sheep increased by 1/6 from the end of 2004 to the end of 2005
We still know nothing about the other animals
=>Not sufficient

Ans: A
_________________

PS: Like my approach? Please Help me with some Kudos. :-)

Re: At the end of 2004, a certain farm had 24 hens, 12 cows, 30   [#permalink] 25 Jun 2013, 07:16
    Similar topics Author Replies Last post
Similar
Topics:
2 Experts publish their posts in the topic On a certain farm the ratio of horses to cows is 7:3. If the obs23 5 15 Apr 2013, 03:40
3 Experts publish their posts in the topic A farm has chickens, cows and sheep. There are three times manalq8 6 12 Jan 2012, 07:00
4 Of the 60 animals on a certain farm, 2/3 are either pigs or cows neeraj.kaushal 3 05 Jul 2008, 20:09
31 Experts publish their posts in the topic Of the 60 animals on a certain farm, 2/3 are either cows or DenisSh 45 11 Oct 2009, 23:59
How many zeros does 100! end with? 20 24 25 30 32 from the Titleist 4 09 Dec 2004, 20:55
Display posts from previous: Sort by

At the end of 2004, a certain farm had 24 hens, 12 cows, 30

  Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.